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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7)

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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Loans (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 605,854		$ 593,944
Unearned premiums and deferred loan fees and costs, net	751		974
Allowance for loan losses	(7,473)	(7,565)	(7,794)	(8,065)	(7,803)	(7,764)
Loans, net	599,132		587,124
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	243,748		245,764
Allowance for loan losses	(3,244)	(3,289)	(3,406)	(3,517)	(3,343)	(3,504)
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	198,017		185,345
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	33,910		34,352
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	128,450		126,052
Allowance for loan losses	(2,072)	(2,077)	(2,167)	(2,734)	(2,808)	(2,712)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,729		2,431
Allowance for loan losses	$ (12)	$ (11)	$ (13)	$ (14)	$ (16)	$ (17)